RESUMO
: Gestational diabetes mellitus (GDM) associates with fetal endothelial dysfunction (ED), which occurs independently of adequate glycemic control. Scarce information exists about the impact of different GDM therapeutic schemes on maternal dyslipidemia and obesity and their contribution to the development of fetal-ED. The aim of this study was to evaluate the effect of GDM-treatments on lipid levels in nonobese (N) and obese (O) pregnant women and the effect of maternal cholesterol levels in GDM-associated ED in the umbilical vein (UV). O-GDM women treated with diet showed decreased total cholesterol (TC) and low-density lipoproteins (LDL) levels with respect to N-GDM ones. Moreover, O-GDM women treated with diet in addition to insulin showed higher TC and LDL levels than N-GDM women. The maximum relaxation to calcitonin gene-related peptide of the UV rings was lower in the N-GDM group compared to the N one, and increased maternal levels of TC were associated with even lower dilation in the N-GDM group. We conclude that GDM-treatments modulate the TC and LDL levels depending on maternal weight. Additionally, increased TC levels worsen the GDM-associated ED of UV rings. This study suggests that it could be relevant to consider a specific GDM-treatment according to weight in order to prevent fetal-ED, as well as to consider the possible effects of maternal lipids during pregnancy.
Assuntos
Diabetes Gestacional/dietoterapia , Dislipidemias/dietoterapia , Troca Materno-Fetal/fisiologia , Obesidade/dietoterapia , Veias Umbilicais/fisiopatologia , Adulto , Peso ao Nascer/fisiologia , Glicemia/análise , Índice de Massa Corporal , Peso Corporal/fisiologia , Colesterol/sangue , Colesterol/metabolismo , Estudos Transversais , Diabetes Gestacional/sangue , Diabetes Gestacional/diagnóstico , Diabetes Gestacional/metabolismo , Dieta com Restrição de Carboidratos , Dislipidemias/sangue , Dislipidemias/etiologia , Dislipidemias/fisiopatologia , Endotélio Vascular/fisiopatologia , Feminino , Humanos , Recém-Nascido , Lipoproteínas LDL/sangue , Lipoproteínas LDL/metabolismo , Masculino , Pessoa de Meia-Idade , Obesidade/sangue , Obesidade/metabolismo , Obesidade/fisiopatologia , Circulação Placentária/fisiologia , Gravidez , Estudos Retrospectivos , Adulto JovemRESUMO
OBJECTIVE: Pregestational maternal obesity (PGMO) associates with foetoplacental vascular endothelial dysfunction and higher risk for insulin resistance in the neonate. We characterised the PGMO consequences on the insulin response of the human foetoplacental vasculature. METHODS: Umbilical veins were from pregnancies where the mother was with PGMO (body mass index 30-42.3â¯kg/m2, nâ¯=â¯33) or normal pregestational weight (PGMN) (body mass index 19.5-24.4â¯kg/m2, nâ¯=â¯21) with total gestational weight gain within the physiological range. Umbilical vein ring segments were mounted in a myograph for isometric force measurements. Primary cultures of human umbilical vein endothelial cells were used in passage 3. Vessel rings and cells were exposed to 1â¯nmol/L insulin (20â¯min) in the absence or presence of 100⯵mol/L NG-nitro-l-arginine methyl ester (inhibitor of nitric oxide synthase, NOS). RESULTS: Vessel rings from PGMO showed reduced nitric oxide synthase-activity dependent dilation to insulin or calcitonin-gene related peptide compared with PGMN. PGMO associated with higher inhibitor phosphorylation of the insulin receptor substrate 1 (IRS-1) and lower activator phosphorylation of protein kinase B/Akt (Akt). Cells from PGMO also showed lower nitric oxide level and reduced activator serine1177 but increased inhibitor threonine495 phosphorylation of endothelial nitric oxide synthase (eNOS) and saturable transport of l-arginine. HUVECs from PGMO were not responsive to insulin. CONCLUSION: The lack of response to insulin by the foetoplacental endothelium may result from reduced IRS-1/Akt/eNOS signalling in PGMO. These findings may result in higher risk of insulin resistance in neonates to PGMO pregnancies.
Assuntos
Endotélio Vascular/fisiopatologia , Insulina , Obesidade/fisiopatologia , Complicações na Gravidez/fisiopatologia , Veias Umbilicais/fisiopatologia , Adulto , Arginina/metabolismo , Estudos de Casos e Controles , Células Endoteliais/metabolismo , Feminino , Células Endoteliais da Veia Umbilical Humana , Humanos , Recém-Nascido , Proteínas Substratos do Receptor de Insulina/metabolismo , Miografia , Gravidez , Cultura Primária de Células , Adulto JovemRESUMO
OBJECTIVE: The objective of the study was to establish the risk of fetal death in early-onset growth-restricted fetuses with absent or reversed end-diastolic velocities in the umbilical artery or ductus venosus. DATA SOURCES: A systematic search was performed to identify relevant studies published in English, Spanish, French, Italian, or German using the databases PubMed, ISI Web of Science, and SCOPUS, without publication time restrictions. STUDY ELIGIBILITY CRITERIA: The study criteria included observational cohort studies and randomized controlled trials of early-onset growth-restricted fetuses (diagnosed before 34 weeks of gestation), with information on the rate of fetal death occurring before 34 weeks of gestation and absent or reversed end-diastolic velocities in the umbilical artery and/or ductus venosus. STUDY APPRAISAL AND SYNTHESIS METHODS: For quality assessment, 2 reviewers independently assessed the risk of bias using the Newcastle-Ottawa Scale for observational studies and the Cochrane Collaboration's tool for randomized trials. For the meta-analysis, odds ratio for both fixed and random-effects models (weighting by inverse of variance) were used. Heterogeneity between studies was assessed using tau2, χ2 (Cochrane Q), and I2 statistics. Publication bias was assessed by a funnel plot for meta-analyses and quantified by the Egger method. RESULTS: A total of 31 studies were included in this meta-analysis. The odds ratios for fetal death (random-effects models) were 3.59 (95% confidence interval, 2.3-5.6), 7.27 (95% confidence interval, 4.6-11.4), and 11.6 (95% confidence interval, 6.3-19.7) for growth-restricted fetuses with umbilical artery absent end-diastolic velocities, umbilical artery reversed end-diastolic velocities, and ductus venosus absent or reversed end-diastolic velocities, respectively. There was no substantial heterogeneity among studies for any of the analyses. CONCLUSION: Early-onset growth-restricted fetuses with either umbilical artery or ductus venosus absent or reserved end-diastolic velocities are at a substantially increased risk for fetal death.
Assuntos
Morte Fetal , Retardo do Crescimento Fetal/epidemiologia , Artérias Umbilicais/fisiopatologia , Veias Umbilicais/fisiopatologia , Velocidade do Fluxo Sanguíneo , Diástole , Feminino , Retardo do Crescimento Fetal/fisiopatologia , Idade Gestacional , Humanos , Gravidez , Risco , Ultrassonografia Pré-Natal , Artérias Umbilicais/diagnóstico por imagem , Veias Umbilicais/diagnóstico por imagemAssuntos
Embolização Terapêutica , Encefalopatia Hepática/terapia , Circulação Hepática , Veia Porta/fisiopatologia , Veias Umbilicais/fisiopatologia , Idoso , Feminino , Encefalopatia Hepática/diagnóstico , Encefalopatia Hepática/etiologia , Encefalopatia Hepática/fisiopatologia , Hepatite Autoimune/complicações , Humanos , Cirrose Hepática/etiologia , Flebografia/métodos , Pressão na Veia Porta , Veia Porta/diagnóstico por imagem , Recidiva , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Veias Umbilicais/diagnóstico por imagemRESUMO
OBJECTIVES: The aim of this study was to determine the correlation between ductus venosus (DV) Doppler velocimetry and fetal cardiac troponin T (cTnT). STUDY DESIGN: Between March 2007 and March 2008, 89 high-risk pregnancies were prospectively studied. All patients delivered by cesarean section and the Doppler exams were performed on the same day. Multiple regression included the following variables: maternal age, parity, hypertension, diabetes, gestational age at delivery, umbilical artery (UA) S/D ratio, diagnosis of absent or reversed end-diastolic flow velocity (AREDV) in the UA, middle cerebral artery (MCA) pulsatility index (PI), and DV pulsatility index for veins (PIV). Immediately after delivery, UA blood samples were obtained for the measurement of pH and cTnT levels. Statistical analysis included the Kruskal-Wallis test and multiple regressions. RESULTS: The results showed a cTnT concentration at birth >0.05 ng/ml in nine (81.8%) of AREDV cases, a proportion significantly higher than that observed in normal UA S/D ratio and UA S/D ratio >p95 with positive diastolic blood flow (7.7 and 23.1%, respectively, p<0.001). A positive correlation was found between abnormal DV-PIV and elevated cTnT levels in the UA. Multiple regression identified DV-PIV and a diagnosis of AREDV as independent factors associated with abnormal fetal cTnT levels (p<0.0001, F(2.86)=63.5, R=0.7722). CONCLUSION: DV-PIV was significantly correlated with fetal cTnT concentrations at delivery. AREDV and abnormal DV flow represent severe cardiac compromise, with increased systemic venous pressure, and a rise in right ventricular afterload, demonstrated by myocardial damage and elevated fetal cTnT.
Assuntos
Feto/irrigação sanguínea , Coração/fisiopatologia , Troponina T/sangue , Artérias Umbilicais/fisiopatologia , Veias Umbilicais/fisiopatologia , Adulto , Biomarcadores/sangue , Velocidade do Fluxo Sanguíneo/fisiologia , Estudos Transversais , Feminino , Humanos , Recém-Nascido , Fluxometria por Laser-Doppler , Artéria Cerebral Média/fisiopatologia , Insuficiência Placentária/fisiopatologia , Gravidez , Estudos ProspectivosRESUMO
OBJECTIVE: Ductus venosus and inferior vena cava flow velocity was assessed in fetuses in isoimmunized pregnancies. METHODS: Examination of 61 fetuses aged 27 to 35 weeks from Rh-erythrocyte antigen isoimmunized women was carried out from June 1999 to June 2004. All fetuses were submitted to the examination of ductus venosus and inferior vena cava flow velocity. Blood samples were collected to determine hemoglobin values and hemoglobin concentration deficits. Accordingly, fetuses were grouped as follows: non-anemic; mildly anemic; moderately anemic and severely anemic fetuses. Comparison of the variation of average flow velocity in the inferior vena cava and ductus venosus across the four groups was carried out using the chi-square test. RESULTS: Inferior vena cava flow velocity was found to be altered in 3.8% of non-anemic fetuses; in 3.1% of the mildly anemic, in 40.0% of those moderately anemic; and in 76.0% of the severely anemic ones. Alteration in ductus venosus flow velocity, in turn, was identified in 7.7% of non-anemic fetuses; 3.1% of mildly anemic; 32.5% of moderately anemic and 68.0% of those severely anemic. Results were statistically significant with p < 0.001. CONCLUSION: The study shows that alteration of flow velocity in the inferior vena cava and ductus venosus increased with the severity of anemia.
Assuntos
Anemia/fisiopatologia , Doenças Fetais/fisiopatologia , Feto/irrigação sanguínea , Isoimunização Rh/fisiopatologia , Adulto , Velocidade do Fluxo Sanguíneo , Cordocentese , Estudos Transversais , Feminino , Idade Gestacional , Humanos , Gravidez , Segundo Trimestre da Gravidez , Terceiro Trimestre da Gravidez , Ultrassonografia , Veias Umbilicais/diagnóstico por imagem , Veias Umbilicais/fisiopatologia , Veia Cava Inferior/diagnóstico por imagem , Veia Cava Inferior/fisiopatologiaRESUMO
OBJETIVO: Avaliar a velocidade de fluxo na veia cava inferior e no ducto venoso em fetos, nas gestações isoimunizadas. MÉTODOS: De junho de 1999 a junho de 2004, foram avaliados 61 fetos, entre 27 e 35 semanas, de gestantes portadoras de isoimunização por antígenos eritrocitários. Em todos os fetos foram avaliadas as velocidades de fluxo na veia cava inferior e no ducto venoso. Obteve-se amostra de sangue fetal para determinação dos valores da hemoglobina e calculou-se o déficit da concentração de hemoglobina. Esses fetos foram divididos em quatro grupos, de acordo com o déficit da concentração de hemoglobina: fetos não anêmicos, anêmicos leves, anêmicos moderados e anêmicos graves. Utilizou-se o teste Qui-quadrado para comparar os quatro grupos de fetos quanto à proporção da alteração da velocidade média de fluxo na veia cava inferior e no ducto venoso. RESULTADOS: A velocidade de fluxo na veia cava inferior estava alterada em 3,8 por cento dos fetos não anêmicos, em 3,1 por cento dos fetos com anemia leve, em 40 por cento dos anêmicos moderados e em 76 por cento dos fetos com anemia grave. Já a velocidade de fluxo no ducto venoso estava alterada em 7,7 por cento dos fetos não anêmicos, em 3,1 por cento dos fetos com anemia leve, em 32,5 por cento dos anêmicos moderados e em 68 por cento dos fetos com anemia grave. O valor p foi inferior a 0,001. CONCLUSÃO: Verificou-se aumento da freqüência de alteração da velocidade de fluxo na veia cava inferior e no ducto venoso à medida que a anemia se agravava.
OBJECTIVE: Ductus venosus and inferior vena cava flow velocity was assessed in fetuses in isoimmunized pregnancies. METHODS: Examination of 61 fetuses aged 27 to 35 weeks from Rh-erythrocyte antigen isoimmunized women was carried out from June 1999 to June 2004. All fetuses were submitted to the examination of ductus venosus and inferior vena cava flow velocity. Blood samples were collected to determine hemoglobin values and hemoglobin concentration deficits. Accordingly, fetuses were grouped as follows: non-anemic; mildly anemic; moderately anemic and severely anemic fetuses. Comparison of the variation of average flow velocity in the inferior vena cava and ductus venosus across the four groups was carried out using the chi-square test. RESULTS: Inferior vena cava flow velocity was found to be altered in 3.8 percent of non-anemic fetuses; in 3.1 percent of the mildly anemic, in 40.0 percent of those moderately anemic; and in 76.0 percent of the severely anemic ones. Alteration in ductus venosus flow velocity, in turn, was identified in 7.7 percent of non-anemic fetuses; 3.1 percent of mildly anemic; 32.5 percent of moderately anemic and 68.0 percent of those severely anemic. Results were statistically significant with p < 0.001. CONCLUSION: The study shows that alteration of flow velocity in the inferior vena cava and ductus venosus increased with the severity of anemia.
Assuntos
Humanos , Feminino , Gravidez , Adulto , Anemia/fisiopatologia , Doenças Fetais/fisiopatologia , Feto/irrigação sanguínea , Isoimunização Rh/fisiopatologia , Ultrassonografia Doppler , Ultrassonografia Pré-Natal , Velocidade do Fluxo Sanguíneo , Cordocentese , Estudos Transversais , Idade Gestacional , Segundo Trimestre da Gravidez , Terceiro Trimestre da Gravidez , Veias Umbilicais/fisiopatologia , Veias Umbilicais , Veia Cava Inferior/fisiopatologia , Veia Cava InferiorRESUMO
OBJECTIVES: To investigate the possibility of predicting acidemia at birth in pregnancies with placental insufficiency by Doppler velocimetry of the ductus venosus and to establish the best parameter and cut-off points in this prediction. METHODS: This was a prospective cross-sectional study, involving 47 single pregnancies with placental insufficiency after 26 weeks of gestation, carried out at the "Hospital São Paulo (UNIFESP) and Maternidade-Escola Assis Chateaubriand (UFC)". Placental insufficiency was defined as the umbilical artery pulsatility index above the 95th percentile for gestational age. Fetuses with chromosomal or structural anomalies were excluded. The time interval between the Doppler velocimetry and the birth was of less than 24 hours. The umbilical arterial blood samples were collected immediately after birth. Acidemia was defined as umbilical arterial pH < 7.2 in the absence of uterine contractions and < 7.15 in the presence of contractions. Metabolic or mixed acidemia at birth was considered pathological. Receiver operating characteristics (ROC) curves were calculated for S, D and A-velocities, pulsatility index for veins and the S/A ratio and (S-A)/S ratio of the ductus venosus. Parameters were compared using the MacNemar Test RESULTS: S, D and A-velocities of the ductus venosus were poor predictors of acidemia at birth. The pulsatility index for veins (area under the curve 0.79, p=0.003), S/A ratio and (S-A)/S ratio (area under the curve 0.818, p=0.001) of the DV were strongly related to fetal acidemia. The cut-off points calculated were: pulsatility index for veins = 0.76; S/A ratio = 2.67 and (S-A)/S ratio = 0.63. CONCLUSIONS: The angle-independent indices of the DV Doppler are adequate for the diagnosis of fetal acidemia in gestations with placental insufficiency. No statistically significant differences were observed between these parameters.
Assuntos
Acidose/fisiopatologia , Fluxometria por Laser-Doppler , Insuficiência Placentária/fisiopatologia , Artérias Umbilicais/fisiopatologia , Veias Umbilicais/fisiopatologia , Acidose/sangue , Acidose/diagnóstico , Adolescente , Adulto , Velocidade do Fluxo Sanguíneo , Métodos Epidemiológicos , Feminino , Humanos , Recém-Nascido , Insuficiência Placentária/sangue , GravidezRESUMO
BACKGROUND: The hemodynamical effect of the collateral portosystemic circulation upon the portal system has not yet been fully understood. The US-Doppler made possible the non-invasive study of the portal system by evaluating the parameters: flow direction, diameter and flow velocity in it's vessels. AIMS: To study the paraumbilical vein as a collateral portosystemic pathway and identify patterns for appraising its hemodynamic importance to the portal system. METHOD: US-Doppler study of the portal system of 24 patients with Mansoni's hepatosplenic schistosomic portal hypertension, previous esophagic variceal bleeding and patent paraumbilical vein with hepatofugal flow. The diameter and the mean flow velocity were measured in the paraumbilical vein and so were the mean flow velocity in the portal vein, right and left portal branches. The Pearson test (linear correlation) was applied to the portal vein's mean flow velocity and the paraumbilical vein's diameter and mean flow velocity. The patients were divided in four groups: D1-paraumbilical vein with diameter < 0.68 cm (n = 14), D2-paraumbilical vein with diameter > or = 0.68 cm (n = 10), V1-paraumbilical vein with mean flow velocity < 18.41 cm/seg (n = 13) and V2-paraumbilical vein with mean flow velocity > or = 18.41 cm/seg (n = 11). The mean flow velocity in the portal vein, right and left portal branches of the four groups were compared. RESULTS: The paraumbilical vein diameter was 0.68 +/- 0.33 cm (range: 0.15-1.30 cm) and the mean flow velocity was 18.41 +/- 11.51 cm/seg (range: 5.73-38.20 cm/seg). The linear correlation between the portal vein's mean flow velocity/paraumbilical vein diameter and the paraumbilical vein's mean flow velocity showed r = 0.504 and r = 0.735, respectively. In the group D2 there was an increase in the mean flow velocity in the portal vein (17.80 +/- 3.42/22.30 +/- 7.67 cm/seg) and in the left portal branch (16.00 +/- 4.73/22.40 +/- 7.90 cm/seg). In the group V2 there was an increase in the mean flow velocity in the portal vein (16.31 +/- 3.49/21.96 +/- 5.89 cm/seg) and in the left portal branch (14.22 +/- 4.41/21.94 +/- 7.20 cm/seg). There was no change in the right portal branch (13.67 +/- 5.74/15.43 +/- 3.43 cm/seg). CONCLUSIONS: In portal hypertension due to hepatosplenic schistosomiasis, the patent paraumbilical vein, with hepatofugal flow, diameter > or = 0.68 cm and mean flow velocity > or = 18.41 cm/seg causes an increase of the mean flow velocity in the portal vein and left portal branch. The best US-Doppler parameter to appraise the paraumbilical vein influence upon the portal system is the mean flow velocity. The correlation between the increase in portal vein's mean flow velocity is stronger with the paraumbilical vein's mean flow velocity than with its diameter. The increase in the portal vein's and left portal branch's mean flow velocity may be understood as the paraumbilical vein's hemodynamic influence upon the portal system. An active portosystemic collateral pathway increases the mean flow velocity in the vein's segment proximal to its point of origin.
Assuntos
Hipertensão Portal/diagnóstico por imagem , Hepatopatias Parasitárias/diagnóstico por imagem , Esquistossomose mansoni/fisiopatologia , Veias Umbilicais/diagnóstico por imagem , Hemodinâmica , Humanos , Hipertensão Portal/fisiopatologia , Hepatopatias Parasitárias/fisiopatologia , Veia Porta/diagnóstico por imagem , Fluxo Sanguíneo Regional , Esquistossomose mansoni/diagnóstico por imagem , Ultrassonografia Doppler , Veias Umbilicais/fisiopatologiaRESUMO
This report describes a case of reverse flow in the umbilical vein and ductus venosus during atrial contraction of a fetus at 12 weeks of gestation with increased nuchal translucency (9.1 mm). In addition, Doppler velocimetry detected high retrograde flow in the inferior vena cava. Cytogenetic analysis of chorionic villi revealed trisomy 9. We suggest that these findings may be a first trimester sign of chromosomal and cardiac abnormalities in the fetus.